Water-cooled hollow shaft for ore-roasting furnaces.



2 SHEETSSHEET I.

Patented Feb. 29, 1916.

APPLICATION HLED JAN 3 1912 E. JENSEN-VALDAL. WATER COOLED HOLLOW SHAFT FOR ORE ROASTING FURNACES.

E. JENSEN-VALDAL. WATER COOLED HOLLOW SHAFT FOR ORE ROASTING FURNACES.

APPLICATION HLED JAN. 31 1912- 1,173,354. Patented Feb. 29,1916.

I 2 SHEETS SHEET 2.

[nven ior THE COLUMBlA PLANOGRAPH 00., WASHINGTON, D. c

ERNST JENSEN'-VALDAL, OF COPENHAGEN, DENMARK, ASSIGNOR 'I'O AKTIESELSKABET DANSK SVOVLSYRE- & SUPERPHOSPHAT-FABRIK, OF COPENHAGEN, DENMARK.

WATER-000L131) HOLLOW SHAFT FOR ORE-ROASTING FURNACES.

Specification of Letters Patent.

Patented Feb. 29, 1916.

Application filed January 3, 1912. Serial No. 669,282.

To all whom it may concern:

Be it known that I, ERNST JENSEN-VALDAL, a subject of the King of Denmark, and resident of Copenhagen, Denmark, have invented certain new and useful Improvements in ater-Cooled Hollow Shafts for Ore-Roasting Furnaces, of which the following is a. specification.

The present invention relates to a modifled construction of the known water-cooled hollow-shafts with water-cooled stirringarms which are used in mechanical furnaces for roasting pyrites and other ores.

In the previously known water cooled hollow-shafts with stirring-arms the cooling water is led in at the foot of the hollowshaft, wherefrom it is to be distributed into all of the stirring-arms; the heated Water then leaves the hollow-shaft at top; this water-cooling principle, however, is not very appropriate, because in the upper stories where most heat is developed by the burning pyrite, the arms will not be sufliciently cooled, the cooling-water received by these arms being already much heated by its streaming from below up through the hollow-shaft and through the arms in the lower stories of the furnace. Consequently an unduly great quantity of incrustation will be deposited inside the arms in the upper stories, which will further reduce the effect of the cooling water. At breaking of an arm the water will rush out into the furnace from a hole as large as the inner cross section of the arm, and the supply of water to the hollow-shaft as well as to all of the arms will have to be stopped as soon as possible, whereby there is the risk of destruction of the packings between the shaft and the arms, the temperature being here unduly quickly augmented owing to the stopping of the cooling-water; therefore the stopping of the working of the furnace and mounting of new arms instead of the broken arms often incur replacing of a couple of the other arms. Therefore the aim of the present invention has been partly a most effective cooling of the hollow shaft and of each of the arms, partly a device by which in the event of breaking-of an arm it is only needed to stop the supply of water to the broken arm, and whereby it is possible, while a new arm is mounted from outside, through one of the furnace doors to confor incurring the circulation of the coolingwater. In order to be able to regulate the quantity of cooling-Water, the discharges are provided with thermometers and discharge-cocks.

The inlet-pipe for the cooling-water to an arm is led to one chamber of a cast ironboX arranged in the shaft opposite to the arm in question, which boX by a partitionwall is divided'into two compartments and which is open toward the arm, which in its longitudinal direction is divided into two chambers by means of a corresponding partition-wall; this is interrupted toward the free end of the arm, so that the cooling water may here run back through the chamber on the other side of the partition-wall in the arm and from thence farther into the other compartment of the cast iron box, from whence the discharge-pipe leads the heated water farther out ofthe furnace.

Through the above described device it is possible in the event of breaking of an arm to stop the supply of the cooling-water t0 the broken arm, without stopping the supply to the other arms and to the hollowshaft. Therefore in the event of breaking of an arm the stopping of the cooling-water can be limited to the arm in question, when after having stopped the furnace in order to remove the broken arm from the same,-

the working of the furnace can be continued, until a repair is found convenient.

In the accompanying drawing are shown 3 sections of a water-cooled hollow-shaft with arms according to the present invention.

In Figure 1 is shown a vertical section through a hollow-shaft with two pipe-arms and inlet and discharge for the coolingwater according to the above described cated by means of arrows.

the roasting furnace and the cooling apparatus installed in the same. I

In Fig. 1 A is the coolingwater-pipe which leads the water to a cooling-watertank (1' which is arranged on the upper end of the hollow-shaft B, from which tank the Water is distributed to the inlet-pipe D for the hollow-shaft and to the inlet-pipes for the arms, of which is only shown the pipe E belonging to a single arm. The pipe D leads almost to the bottom of the hollow-shaft, from whence the water streams back up through the hollow-shaft and through the discharge pipe F, which in Fig. l is shown on the rearmost inner side of the shaft; from the pipe F the water runs out into the ring shaped water-vessel G, which is common for all the discharges. The motion of the eooling-water down through the pipe I). and up through the hollow-shaft is indi- Through the pipe E the corresponding inlet-pipes for all of the other arms which are not seen in the figure, the cooling-water streams into one compartment H of the. cast-iron box J,

which in the figure is shown cast integral with the shaft, but may also be cast separately and connected to the shaft in a known manner from the compartment H the water runs out along one side of the partition-wall in the arm K, which is closed with a screw plug L, runs back along the other side of the partition-wall, which is shown vertical in the figure, but may also have any other positiongpfrom the arm the water streams through the other compartment M of the cast iron box, which compartment with regard to this arm is shown in section in Fig. 2 and with regard to the oppositely arranged armis represented by R in Figs. 1 and: 2-; from the other compartment of the cast, iron box the water flows through the discharge pipe N which is provided with a thermometer O and a regulation-cock P, as shown in Fig. 1, out into the ring-shaped water-vessel Gr. A discharge pipe and its complemental regulation cock are provided for compartmentM. The pipes E and N are each provided with stops. 8 which are adapted to prevent water from flowing into the pipes should one of the arms K break. The motion of the water through the stir ring-arms is indicated inv F igs. I and 2 by arrows.

Having now described my said'invention and in what manner the same is to be performed I declare that what I claim and desire to secure by Letters Patent of U. S. A. is

1. In a roasting furnace in combination, a hollow shaft, hollow stirring arms projecting from said shaft, individual water supplying pipes for each of said arms adapted to be closed independently of the remainder of said pipes, a water tank secured to said shaft,individual discharge pipes for each of said arms, means for regulating the flow of the water through each of said discharge pipes, and a water vessel adapted to receive the discharge from said discharge pipes, substantially as described.

2. In a roasting furnace, in combination, a hollow shaft, hollow stirring arms projecting from said shaft, a water tank secured to said shaft, individual water supplying pipes for said hollow shafts'and for each of said arms, the pipes for each of said arms being adapted to be closed independently of the remainder of said pipes, individual discharge pipes from each of said arms and from said hollow shaft, means for regulating the flow" of water through each of said discharge pipes, and a water vessel adapted to receive'the discharge from said discharge pipes, substantially as described.

3. In a roasting furnace, in combination, a hollow shaft, a tank secured to said shaft, inwardly projecting boxes within said shaft, hollow stirring arms mounted in connection with said boxes, individual water supplying In testimony whereof I have affiXed my signature in presence of two witnesses.

ERNST J ENSEN-VALDAL Witnesses VIceo BLoM, CECIL VILHELM Sol-ION.

copies of this patent may; be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. C. 

